52 ANATOMY OF VERTEBRATES. 



tendon, along the carpus ; this first detaches a tendon to the 

 ungual phalanx of the pollex, and, at the metacarpus, divides into 

 the four tendons similarly inserted into the four long digits. In 

 each the insertion, fig. 36, b, is into the lever-like process from 

 the palmar part of the bone of the last phalanx. It is this muscle 

 which overcomes the retractile force of the elastic ligaments, ib. 

 a, of the claws, and concentrates the power of all five upon the 

 part seized. There is no separate ' flexor longus pollicis.' 



In the hind limb of Felines, the psoas and iliacus are 

 more obviously parts of the same muscle than in Man : a fasciculus 

 of the i psoas ' sends a tendon to the pubis ; but the main body 

 of the muscle acts upon the inner trochanter. In the Cat a 

 detachment of the small ectojxluteus descends to be inserted into 

 the patella. The much longer mesogluteus has five origins from 

 lumbar, sacral and caudal vertebrae, and from the crista ilii : its 

 tendon goes to the great trochanter. The ' gracilis ' is relatively 

 large. The muscle at the foremost part of the thigh, in Felines, 

 answers to the ' sartorius ' and ( rectus femoris ;' there is also a 

 ' tensor fasciae,' which sends an aponeurosis over the fore part of 

 the knee-joint and a tendon to the inner part of the head of the 

 tibia. The ' biceps flexor cruris ' receives a slender accessory 

 fascicule from an anterior caudal vertebra ; besides its normal in- 

 sertion it is continued by fascia into the ( tendo achillis.' In the 

 Lion, a special muscle, ' caudo-femoralis,' from the same vertebrae 

 is inserted by its own long tendon into the outer condyle of the 

 femur. The Bear has not the latter muscle. The largest part 

 of the ( gastrocnemii ' muscles is at or near to their femoral origins : 

 the tendons of each are at first distinct, and finally blend by ex- 

 pansions which spread over the calcaneum. The soleus is small, 

 and rises from the fibula: its tendon unites with that of the 

 gastrocnemius externus. The tendon of the ' plantaris ' combines 

 with that of the ' short flexor ' of the toes to augment the power 

 of bending their phalanges : its fleshy part is relatively much 

 greater than in Man. 



§ 200. Muscles of Quadrumana. — In this series, up to the apes, 

 the panniculus carnosus exists ; but is reduced to a thin sheet of 

 carneous fibres from the dorso-lumbar fascia, spreading over the 

 latissimus dor si, and again degenerating to fascia attached to the 

 inner side of the humerus. The e platysma myo'ides ' begins to be 

 defined, in the Aye-aye, as a pair of broad thin layers, arising from 

 pectoral and clavicular fascia, and ascending over the front and 

 sides of the neck, mandibular rami, and cheeks. In the Orangs 

 and Chimpanzees it supports the large cervico-pectoral air-sac 

 communicating with the larynx. 



